Oil Starvation

[ajmac]

I am always intersted in failure modes and the following photo shows what happens to a Turbine bearing on a thirty+ year old machine that has been under maintained in the North Sea (not on the platform I am on now, this was taken last year further north). The oil feed line blocked up and with no temperature monitoring or vibration monitoring system installed on an engine designed in the late 1960s the machine continued to run at full power until a mechanical overspeed trip unit vibrated off its seat and stopped the unit! The journal and cap had got so hot they were blue, the journal had extruded out into the oil groove machined into the bearing housing, on stopping, the weight of the overhung turbine disks bent the shaft. It all had to be scrapped, new housing and rotor installed and it's running again now, helping the UK balance of payments :-)